Mega/NeoPixel light system for carnival ride.

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wes h
 
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Mega/NeoPixel light system for carnival ride.

Post by wes h »

My son (electrical engineer) is helping me with mounting a new lighting system on my carnival ride, the Orbiter 2000. We have the Adafruit mega controller and 2 ea x 5 meter strips of Adafruit digital RGB weatherproof 30 per meter, black neopixel strips. The ride is engine driven and starts with a standard car type lead-acid 12 VDC battery. There is no 115VAC available, just the 12VDC battery, so we need to use the power available. We would like to avoid Inverters or additional batteries and battery chargers if possible because they would cause electrical inefficiences and additional equipment to maintain. It would be much better if we can make the existing battery/alternator system work. We didn't find any product you sell that would do the job so we tried one to reduce power from 12VDC to 5VDC. It is $14.88 from EBAY: waterproof, 12v/24v to 5 v, 10 Amp, 50W DC/DC step down power converter regulator. It works fine on the system battery until the engine is started up, but soon as the engine starts and the alternator kicks in it lets voltage spikes through that fry the first light of the strip and the whole strip shuts down. Can you recommend another 12vdc to 4 - 5vdc power step-down converter regulator that will work better? Or do you have suggestions of capacitors, surge protectors, or other devices to take care of the spikes so we can use the one we already have? This little carnival ride is going to look really cool with the new exciting Adafruit light system! It's great to be able to program in different color schemes and flashing sequences! Now, all we have to do is solve the problem with the power supply and killer alternator voltage spikes. Can anyone help? We will appreciate any suggestions!

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Franklin97355
 
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Re: Mega/NeoPixel light system for carnival ride.

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adafruit_support_mike
 
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Re: Mega/NeoPixel light system for carnival ride.

Post by adafruit_support_mike »

For this application, plain old LM7805 linear voltage regulators might be the best bet. They aren't very efficient, but the losses will be a drop in the bucket for an engine-powered mechanical system.. especially if you're replacing incandescent lamps with LEDs.

The LM78xx family is ancient, meaning it's solid as a rock. It has good supply rejection, and is easy to obtain in quantity.

If you want a bit more efficiency at the expense of a bit more complexity, use a switching converter to drop from 12v to 7v, then use LM7805s to create smooth 5v rails for the LEDs.

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wes h
 
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Re: Mega/NeoPixel light system for carnival ride.

Post by wes h »

Thank you, Franklin and also Adafruit support Mike, for your suggestions to my problem. The problem is now solved and I am writing this comment in the thread so that others who may experience the same problem may benefit. First of all let me say that the Mega and the neopixel lighting effect on my little carnival ride is excellent! It is an attention grabber and we have programmed in some fun varied routines. Now for what we found as the best solution to our problem. Most of the problem was a result of the fact the engine driving the ride is an old style Ford industrial, same type as used in small old tractors and hay swathers. If I had not had my electrical engineer son, I would have given up and considered the project a failure.

1. First, we found the alternator in the system needed to be replaced. The internal voltage regulator was not functioning correctly.
2. Even though I had just replaced the spark plug wires and spark plugs, we found the wires and plugs were sending impossible voltage spikes. We replaced them with wires and plugs designed to protect radio and electrical systems. That helped and EXTREME amount. Without that change we would have certainly failed to clean up the voltage spikes, and we would have continued to burn out the first light in the string with every test. Oh, by the way, don't throw the light strip away if it burns out. In our experience only the first light burns out. Solder on to the next light and you're back in business.
3. We put a diode between the ignition switch and the input wire on the coil. That really helped, too.
4. We mounted a waterproof plastic box on the ride with a small plywood panel inside, on which was mounted the Mega, the gyro, a couple of circular looking inducers, and a breadboard with some capacitors and resistors to final filter out the rest of the spikes.

Now, thanks to my son, and his oscilloscope electrical testor, we succeeded in mounting your awesome lights!

Again, thank you for your helpful suggestions.

It wasn't easy, but the results are worth it!

Wes

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